缺血心肌梗死模型大鼠中等强度运动后梗死面积的变化

背景：目前对心肌梗死的急性期是否能进行适量的运动,且适量的运动是否对梗死心肌修复与再生有积极的意义,尚存在很大的争议。目的：观察中等强度运动对心肌梗死大鼠梗死面积的影响。方法：将48只SD大鼠随机分为雌、雄训练组和雌、雄对照组,每组12只。结扎大鼠左冠状动脉前降支建立左心室前壁梗死模型。造模24 h,训练组大鼠进行30 min/d的跑台训练,强度为20 m/min,0% grade,共持续12 d;对照组造模后正常饲养。2周后,对大鼠心肌行常规Masson’s Trichrome染色,观察梗死面积和左心室几何参数的变化。结果与讨论：造模2周,训练组和对照组大鼠的死亡率十分接近(22% vs. 20%)。训练组(雌、雄)的心肌梗死面积明显小于对照组(P < 0.05),梗死边缘区室壁厚度大于对照组(P < 0.05),梗死区室壁最小厚度也大于对照组,但差异无显著性意义 (P > 0.05)。说明心肌梗死急性期即进行中等强度的跑台训练不但没有明显降低大鼠的存活率,还能有效减小缺血心肌的梗死面积、改善左心室重构,且上述作用没有性别差异。

Ischemic area changes following moderate training in rat models of ischemic heart

BACKGROUND:It is still controversy regarding to whether moderate training, treated in acute period of myocardial infarction (MI), plays a benefit role in regeneration of myocardial infarction.OBJECTIVE:To investigate the effect of moderate training on infarct areas after myocardial infarction.METHODS: Forty-eight Sprague-Dawley (SD) rats were randomly divided into four experimental groups (male and female trained group and female and male control group), In 24 hours after left anterior descending coronary artery (LAD) ligation, the trained groups were introduced to treadmill training (20 m/min, 0% grade, 30 min/d) for 12 days, while the control groups were fed normally after LAD-ligation. The infarcted size and the geometry of left ventricle (LV) of the trained and control groups were analyzed respectively under the Masson’s Trichrome staining in two-week of MI.RESULTS AND CONCLUSION: It was found that the mortality of trained group was similar to the control group (trained group: 22% vs. control group: 20%). The infarction size of trained group was less than that of control group in two weeks after MI. The difference had statistics significance (P < 0.05). In addition, it was found that the wall thickness of border zone in left ventricle of trained group was longer than control (P < 0.05); while the thickness of infarcted myocardium in LV was greater than that of the control group. All results demonstrated that the moderate-intensity treadmill training treated in acute period of MI did not significantly reduce the survival rate of rats. On the contrary, it was able to reduce the infarcted size of MI. In addition, the moderate treadmill training was able to improve the reconstruction of LV geometry after MI. The effect has no difference on different genders.